1. Field of the Invention
This invention relates to a dental treatment chair and more particularly to a dental treatment chair in which a backrest having therein reeling means for flexible pipes connected to instruments is reclinably titlably mounted on a seat body, and a dispensing controller for controlling compressed air and water to the instruments, a distributing block, and couplings for flexible pipes to each of the instruments are provided in the seat body.
2. Prior Art
The conventional dental treatment chairs are so designed as to control the compressed air and water to be supplied to instruments by a solenoid valve operated by controller, but the controller, which uses numerous large sized solenoid valves, makes it difficult to reduce the overall size of the device. Accordingly, it is almost impossible to install the device in such a small space as the inside of a backrest, with the result that the controller has to be mounted in a seat body which has larger inside space.
However, in the dental treatment chairs having such a controller incorporated into the seat body, the connecting pipes connected to five to six instruments detachably mounted on the shoulder of the backrest had to be introduced into the seat body and connected to the control device. Consequently, repeated reclining movements of the backrest not only caused bending or breaking and shortened the life of each flexible pipe on that "bridge"area of the flexible pipe spanning from the backrest to the seat body, but also had an adverse effect on the supply of compressed air and water. This was a problem. In this manner, in addition to the fact that introduction of the connecting pipes into the seat body proportionately required longer piping and increased passage resistance, it often happened that even if the controller functioned properly, the instruments at the ends of the connecting pipes failed to provide desired efficiency. Besides, the conventional chairs of the kind described made it necessary to check and repair both the backrest containing connecting pipe reeling means therein and the seat body containing the controller therein, thus requiring much trouble. Furthermore, when it came to transporting the chair of the type described, such complicated connection of numerous connecting pipes to the controller inside the seat body made reconnection of the pipes and reassembling of the chair difficult when the chair was transported with the backrest and seat body separated from each other. Accordingly, the chair had to be transported in an assembled form, which resulted in large bulk at an increased transportation charge. The facts described above were some of the accompanying problems of the conventional chairs.